First Pseudohalogen Polymer Electrolyte for Dye-Sensitized Solar Cells Promising for In Situ Photopolymerization

作者：Bella Federico^*; Sacco Adriano; Salvador Gian Paolo; Bianco Stefano; Tresso Elena; Pirri Candido Fabrizio; Bongiovanni Roberta

来源：Journal of Physical Chemistry C, 2013, 117(40): 20421-20430.

DOI：10.1021/jp405363x

The incorporation of selenocianated-based redox couple in a polymer electrolyte for dye-sensitized solar cells is reported for the first time. The pseudohalogen redox mediator was integrated in two kinds of acrylic/methacrylic membranes prepared by photocopolymerization of multifunctional monomers. Before activation, the obtained membranes were transparent, self-standing and flexible, and the physicochemical characterizations of the films showed the formation of highly crosslinked architectures. Membranes were activated by swelling in an optimized solution containing the SeCN-/(SeCN)(2) redox mediator with 4-tert-butylpyridine in acetonitrile, and the electrochemical behavior of the electrolytes revealed fast charge transfer kinetics. The photovoltaic performances of quasi-solid dye-sensitized solar cells were evaluated and compared with the results of the liquid counterpart, showing promising photoharvesting properties. No diminution in photoconversion efficiencies was evidenced in the comparison between solid and liquid cells, demonstrating an optimal kinetics of the redox species in the polymer cage, associated with a noteworthy increase in device durability, as demonstrated by aging tests. In addition, the in situ photopolymerization in the presence of the redox mediator is presented with outstanding results: this process, hardly feasible for the traditional I-/I-3(-) couple (inhibitor of radical polymerization processes), enables at the same time the creation of an excellent electrode/electrolyte interface and the sealing of the device.

• 出版日期2013-10-10